The individual projects outlined in this proposal are aimed at the description of an overall processing architecture of the human neurolinguistic system. As research progresses toward this goal, theoretical notions motivated by empirical studies will be tested with connectionist network models, and concomitantly, predictions from network models will be tested with empirical studies. The desired result is the development of a general theory of cognitive neurolinguistic processing that is both testable and falsifiable. The proposed research and training uses research methods from experimental psychology, speech and language pathology, neuroanatomy and neuropathology, and computer modelling to construct useful cognitive theories of language disorders. Specifically, the project described here proposes to (a) organize a language disorders registry and database and implement it at Presbyterian-University Hospital (PUH); (b) design and execute a study of semantic priming in patients with language disorders; (c) extend an existing prototype connectionist simulator (DYSNET) to permit network lesions of both diffuse and focal types, in order to simulate neurological damage; and (d) perform computer modelling experiments leading to predictions for the design of empirical studies and suggestions for language therapy. Initial modelling experiments will be based on semantic priming data from a study of language disorders in diffuse brain disease. It will first account for the data from normal subjects (independent of age) that supportive context makes sentence completion tasks easier (i.e., faster); subsequently, it will be systematically disrupted (lesioned) to account for the results in the patients with language disorders, and lastly, the model will be examined for approaches to repairing lesioned networks, with attempts to correlate computational strategies and clinical language therapy. In the final two years of the project, the laboratory framework for building computer models should be sufficiently operative to initiate experiments in individualized patient models, with full-scale attempts to use the results of such tests in specific individually tailored language rehabilitation efforts.